Utils

Set of utility functions for Sionna SYS.

sionna.sys.utils.get_pathloss(h_freq, rx_tx_association=None, precision=None)[source]

Computes the pathloss for each receiver-transmitter pair and, if the receiver-transmitter association is provided, the pathloss between each user and the associated base station

Input:

  • h_freq ([…, num_rx, num_rx_ant, num_tx, num_tx_ant, num_ofdm_symbols, num_subcarriers], tf.complex | None (default: None)) – OFDM channel matrix

  • rx_tx_association ([num_rx, num_tx], tf.int32, None (default)) – Its (i,j) element is 1 if receiver i is attached to transmitter j, 0 otherwise

  • precision (None (default) | “single” | “double”) – Precision used for internal calculations and outputs. If set to None, precision is used.

Output:

  • pathloss_all_pairs ([…, num_rx, num_tx, num_ofdm_symbols], tf.float) – Pathloss for each RX-TX pair and across OFDM symbols

  • pathloss_serving_tx ([…, num_ut, num_ofdm_symbols], tf.float) – Pathloss between each user and the associated base station. Only computed if rx_tx_association is provided as input.

sionna.sys.utils.is_scheduled_in_slot(sinr=None, num_allocated_re=None)[source]

Determines whether a user is scheduled in a slot

Input:

  • sinr ([…, num_ofdm_symbols, num_subcarriers, num_ut, num_streams_per_ut], tf.float | None (default)) – SINR for each OFDM symbol, subcarrier, user, and stream. If None, then num_allocated_re is required.

  • num_allocated_re ([…, num_ut], tf.float | None (default)) – Number of allocated resources (streams/REs/PRBs etc.) per user. If None, then sinr is required.

Output:

is_scheduled ([…, num_ut] : tf.bool) – Whether a user is scheduled in a slot

sionna.sys.utils.spread_across_subcarriers(tx_power_per_ut, is_scheduled, num_tx=None, precision=None)[source]

Distributes the power uniformly across all allocated subcarriers and streams for each user

Input:

  • tx_power_per_ut ([…, num_ofdm_sym, num_ut], tf.float) – Transmit power [W] for each user

  • is_scheduled ([…, num_ofdm_sym, num_subcarriers, num_ut, num_streams_per_ut], tf.bool) – Whether a user is scheduled on a given subcarrier and stream

  • num_tx (int | None (default)) – Number of transmitters. If None, it is set to num_ut, as in uplink.

  • precision (None (default) | “single” | “double”) – Precision used for internal calculations and outputs. If set to None, precision is used.

Output:

tx_power ([…, num_tx, num_streams_per_tx, num_ofdm_sym, num_subcarriers], tf.float) – Transmit power [W] for each user, across subcarriers, streams, and OFDM symbols